The proposed research was designed to identify contributions of cognitive factors, including working memory and executive function, to children's performance on both psychoacoustic measures of spectral resolution and speech perception in noise. Past work in adult listeners with hearing loss, including hearing aid and cochlear implant users, has established that psychoacoustic measures of spectral resolution are predictive of speech perception in noise. Relative to adults, children's performance on speech in noise tasks is more variable, even after accounting for the effects of age and audibility. It is hypothesized that some of these differences also may be related to individual differences in spectral resolution, as is the case with adults. However, performance on psychoacoustic measures improves as children develop, and the age at which adult- like performance emerges varies depending on the task. It is not clear precisely which developmental changes contribute to these improvements in performance, and it has not been established the extent to which the relationship of spectral resolution to speech perception in noise is mediated by these developmental and cognitive changes in children. In this study, standard measures of executive function, short-term memory, vocabulary, and non-verbal intelligence will be completed in addition to psychophysical assessments of spectral resolution and speech perception in noise. The overall goal for the proposed research is 1) To characterize in children the relationship between spectral resolution and listener age, hearing loss, executive function, and working memory, and 2) To establish the relationship between spectral resolution and speech perception in noise in children who are hard of hearing controlling for age, hearing loss, executive function, and working memory. Findings from the proposed study are expected to lead to a more complete understanding of what contributes to optimal listener performance in children with and without hearing loss.